Dopamine Modulates Reward-Related Vigor

Beierholm, Ulrik; Guitart-Masip, Marc; Economides, Marcos; Chowdhury, Rumana; Düzel, Emrah; Dolan, Ray; Dayan, Peter

Abstract

Subjects routinely control the vigor with which they emit motoric responses. However, the bulk of formal treatments of decision-making ignores this dimension of choice. A recent theoretical study suggested that action vigor should be influenced by experienced average reward rate and that this rate is encoded by tonic dopamine in the brain. We previously examined how average reward rate modulates vigor as exemplified by response times and found a measure of agreement with the first suggestion. In the current study, we examined the second suggestion, namely the potential influence of dopamine signaling on vigor. Ninety healthy subjects participated in a double-blind experiment in which they received one of the following: placebo, L-DOPA (which increases dopamine levels in the brain), or citalopram (which has a selective, if complex, effect on serotonin levels). Subjects performed multiple trials of a rewarded odd-ball discrimination task in which we varied the potential reward over time in order to exercise the putative link between vigor and average reward rate. Replicating our previous findings, we found that a significant fraction of the variance in subjects’ responses could be explained by our experimentally manipulated changes in average reward rate. Crucially, this relationship was significantly stronger under L-Dopa than under Placebo, suggesting that the impact of average reward levels on action vigor is indeed subject to a dopaminergic influence

Citation

Beierholm, U., Guitart-Masip, M., Economides, M., Chowdhury, R., Düzel, E., Dolan, R., & Dayan, P. (2013). Dopamine Modulates Reward-Related Vigor. Neuropsychopharmacology, 38, 1495-1503. https://doi.org/10.1038/npp.2013.48

• Journal Article Type: Article
• Acceptance Date: Feb 4, 2013
• Online Publication Date: Mar 20, 2013
• Publication Date: Mar 20, 2013
• Deposit Date: Mar 1, 2016
• Publicly Available Date: Sep 12, 2017
• Journal: Neuropsychopharmacology
• Print ISSN: 0893-133X
• Electronic ISSN: 1740-634X
• Publisher: Springer Nature
• Peer Reviewed: Peer Reviewed
• Volume: 38
• Pages: 1495-1503
• DOI: https://doi.org/10.1038/npp.2013.48
• Public URL: https://durham-repository.worktribe.com/output/1418489